Honestly, I like Unity. Or more accurately, I like where they're going with Unity. And I would like the thing itself if it actually worked reliably. But here I am, running the stock version of the biggest Linux distro on popular hardware, and I have to log out and in or reboot roughly daily.
I don't really believe developers are moving to Apple gear because of HN. I believe it because last time I went on a hiring spree, a lot of people said, "Oh, you're running Linux? Do we have to?"
Fair enough, but why not wait to use it until they get there? Daily reliability problems seem like a lot to put up with just for some cool ideas.
Also, I'm not sure how your interviewing experience supports the conclusion "Linux is dead/dying". What it does seem to suggest is "Linux is unpopular", but that has never not been true (on the desktop).
I'm using it because that's part of the default install. At one point I had the time and inclination to spend futzing with stuff to get it to work, but that's not where I'm at. If something isn't ready to use on a desktop OS, they shouldn't ship it.
My previous interviewing experience wasn't like that say, five years ago.
Then you haven't heard of Xubuntu? It's an alternate flavor of Ubuntu that has Xfce as the default install. Here's an iso that will get you basically the exact setup I have, no futzing required: http://xubuntu.org/getxubuntu/
Already installed stock Ubuntu? Install the xubuntu-desktop metapackage (in Synaptic or 'sudo apt-get install xubuntu-desktop'), log out and select "Xubuntu Session" from the login screen. That's it. I did this on my laptop after realizing I didn't want to switch to Unity. (For bonus points you can remove the Unity desktop apps, but that's hardly necessary unless space is at a premium.)
I don't think I'd put up with Linux myself if it was as much of a pain as you seem to think. For me, Xubuntu has been no trouble at all.
I don't really believe developers are moving to Apple gear because of HN. I believe it because last time I went on a hiring spree, a lot of people said, "Oh, you're running Linux? Do we have to?"